A late own goal saw City beat local rivals Yeovil Town 3-2 in Somerset on Wednesday evening, and now they travel to the North East in confident mood.
“We enjoyed the win for about an hour, then our focus turned to recovery yesterday and to Sunderland tomorrow,” said Kirk.
“They are a tough side to break down and it will be a physical game.
“It’s a long trip and we need to prepare properly for it if we are going to go there and get another win.”
The City Women manager insists his side will have to be more clinical if they are to make it two wins on the bounce tomorrow.
He added “We missed an opportunity to get a foothold in the game in the first half against Yeovil. We knew if we got one more goal we would have gone on to a position of real strength.
“To go behind was a real blow, but I’m really pleased with the character shown to come back and I’m delighted with the win.”
Going forward, Kirk says he and the squad are becoming more aware of what they need to work on.
He added: “Elements of the performance were good, but we aren’t kidding ourselves.
“We need to get better at the ugly side of the game in terms of giving away fouls and dealing with long balls but that will come with time.”
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